Arriving in Providence last fall to begin his senior year at Brown University, Luke Woodward didn't have to tell friends what he had done on his summer vacation.

They could tell with one glance. Before the summer Luke had had the body of a woman. Now Luke's breasts were gone, leaving a chest more compatible with Luke's close-cropped hair, baggy jeans and hooded sweatshirts. Some classmates had chipped in to pay for the surgery; to cover the rest, Luke took out loans.

Thanks to the "chest surgery," Luke said, "my quality of life is better." Before, if Luke entered a women's bathroom on campus, "someone might yell, `Oh my God, there's a man here' and call security," he said. "In men's bathrooms I'd have to fold my arms over my chest and hope that no one would notice." Now he and several other Brown students are pressing the university to create more single-stall bathrooms, so students who don't look clearly male or female can avoid harassment.

Luke, a 23-year-old international-relations major, is at the cutting edge of a new kind of campus activism: transgender students and their allies who are convincing colleges to meet needs that include private bathrooms and showers, specialized housing and sports teams on which students who don't identify themselves as either male or female can play. In the last year, transgender students have won accommodations from four East Coast colleges, including Wesleyan, Sarah Lawrence and Smith.

While it isn't clear if the number of students who consider themselves transgender is increasing, their openness - a generation after gay and lesbian students began identifying themselves on campuses - clearly is. Zachary Strassburger, a sophomore at Wesleyan University, in Middletown, Conn., said he "came out" to his parents as "trans" in the 10th grade. (Luke and Zachary, who were born female, asked to be referred to with male pronouns.)

Transgender is a term that describes, and unites, a broad category of people who are uncomfortable in the gender of their birth, said Dr. Ken Zucker, a psychologist who heads a child and adolescent gender-identity clinic in Toronto. Transgender students may also be transsexual - moving from male to female, or female to male with the help of surgery or hormones. (Luke considers himself a "female-to-male trans," no longer fully female but not yet fully male.)

Some transgender students aren't moving between sexes; they're parked somewhere in the middle and prefer to describe themselves as "gender queer" - signifying that they reject the either-or male-female system.

Dr. Zucker said young people claiming a transgender identity "vary in the degree to which they want physical intervention." He added: "Gender identity is distinct from sexual orientation. Gender identity pertains to how a person feels about being male or female; sexual orientation pertains to who are you attracted to sexually."

Zachary, 19, said, "Some people think it's important to be seen as a specific gender; that's not me." There are several dozen "gender queers" among Wesleyan's 2,700 students, said Zachary, who changed his name at 18 and asked that his original first name not be published.

Brown and Sarah Lawrence, in Yonkers, will offer housing for the first time this fall to accommodate transgender students. Wesleyan has assigned a hallway for students who choose to live without designating their gender. A Wesleyan student who was born female but now looks and acts more male than female can have a male roommate. The Wesleyan campus health services clinic no longer requires students to check off "M" or "F" when coming in for a "wellness and sexual health visit." Instead, they are asked on a form to "describe your gender identity history." And this year, the former women's rugby team eliminated "women's" from its name, so that Zachary and several other transgender students would feel comfortable playing. "We don't want people yelling, `Go, girls!' " from the sidelines, Zachary explained.

Mark Nickel, a spokesman for Brown, said members of its incoming freshman class will "fill out a housing questionnaire that will allow them to elect a gender-neutral option." He said the policy "would give transgender students the option to live with other transgender students." And they will be in dorms where there are "lockable bathrooms for use by one person."

At Sarah Lawrence, the assistant dean for residential life, Sarah Cardwell, said the university planned to allow upper-class students to live with students regardless of their sex, and to designate certain bathrooms as "all gender."

"We have a small population of transgender students," Ms. Cardwell said, "and we decided to be proactive, rather than reactive." One of the residents of Wesleyan's transgender hallway, Paige Kruza, is biologically female but looks androgynous. Paige's roommate is male and is extremely respectful, Paige said. When referring to Paige, he uses pronouns that have evolved in the transgender community: "ze" instead of "he" or "she"; "hir" instead of "him" or "her."

Zachary began thinking about the housing issue when he was a senior at a high school in Pittsburgh, where he was harassed because of his masculine appearance. "I ended up threatening to sue the school for not protecting me," he said.

He wanted college to be better. During visits to colleges, he made a point of identifying himself as transgender and asking the schools where he would live as a freshman. "Harvard was the most confused," Zachary said. "They sent me from office to office, not knowing how to react. But I didn't get in anyway."

Wesleyan, by contrast, was the most responsive, Zachary said, adding, "I wanted to come to a college where I'd feel safe."

In his freshman year, he chose to live alone - many Wesleyan freshmen have singles, so not having a roommate didn't stigmatize him. And then he began lobbying for the special hallway. Under existing university policy, a student who was biologically female but dressed and looked male would have to live with another female student. But that could make the female roommate uncomfortable. A male roommate, or another transgender roommate, were better options, Zachary argued.

"Every college student, of any gender, should be able to have the experience of living with a roommate," Zachary said. Now in its first year, 12 students have chosen to live on the freshman hallway, though it's unclear how many identify themselves as transgender.

Zachary himself, now a sophomore, has chosen to room with mostly Jewish students, in one of a number of upper-class residences based around common interests. He also devotes much time to rugby - "my favorite part of college." He said the team had been completely supportive, even paying to replace sweatshirts that said "Women's Rugby" with ones that say "Rugby."

On a sunny afternoon at Wesleyan, Zachary sat on the library steps, chatting with friends who are male, female and transgender. Although transgender people around the country have been victims of hate crimes, students like Zachary say they do not feel discrimination or fear on campus; they know they are lucky to live in environments - small private colleges - with traditions of tolerance.

"It's a very small campus, and everyone knows everyone," Zachary said. "It helps to have a sense of humor if you're trans," he added.

Dr. Davis Smith, the medical director at Wesleyan's student health services, said about a dozen transgender students have identified themselves to him, and the administration, he added, "encouraged me to use a lot of my administrative time" to look at transgender health issues.

"For purposes of sexual health, it doesn't matter if you call yourself male or female," said Dr. Smith, an affable 35-year-old with photos of his wife and daughter in his office. He said that what matters is what a person is doing with his sexual partners.

Dr. Smith added that the transgender students have an influence larger than their numbers. "On this campus," he said, "transgender students are real opinion leaders." He said that as far as he could tell, "there hasn't been any backlash."

At Brown, Sarah Lawrence and Wesleyan, most of the transgender students appear to be women who are fully or partially male-appearing. "I think it's a lot harder if you're male-assigned to come out as transgender," Zachary said. At Hunter College in Manhattan, Dr. Gerald Mallon, a professor in the school of social work and the author of a book on social services for transgender youths, said he knows a number of male-to-female transgender students.

"The transgender community is becoming more vocal and more visible," Dr. Mallon said. "Some are asking for accommodations; others don't need accommodations, but just want to be respected for the gender that they are. I think it may be where the gay movement was 10 or 15 years ago."

At Smith, the women's college in Northampton, Mass., students voted last year to eliminate female pronouns from the student constitution at the request of transgender students. "She" and "her" were replaced with the phrase "the student."

Laurie Fenlason, a college spokeswoman, said that "the vote was undertaken by the students as a gesture of good will toward a handful of fellow students."

But the change was not without controversy. "It contradicts the whole point of having a women's college," said Esi Cleland, a Smith sophomore. "I am opposed to it, because there's something to be said for a women's college, and a lot of us come here because we choose to be in an environment where women are the primary focus."

Students at Barnard have also been grappling with the implications of the fact that some students at a women's college don't identify themselves as women. A recent article in The Columbia Spectator about transgender activism was headlined "Can a Man Attend Barnard College?" "Trans issues," the article reported, "are gaining traction at Barnard."

"We are a women's college," said Suzanne Trimel, the director of public affairs at Barnard. "But if a student began here as a woman and then wanted to change her gender, does that mean we would kick her out of college? No, it doesn't. We are a sensitive and caring community."

"That said, the question has not arisen," Ms. Trimel added. "To the best of our knowledge, no Barnard student has changed gender."

To parents, the phenomenon may be unsettling. Luke says his father's reaction was, "I got married at 25, and that was too young." His point was that changing genders is a big decision for a young person to make, Luke explained. But Luke said he isn't worried that his chest surgery may be irreversible. "I don't know who I'm going to be," he said, "but I can integrate the decisions I make into the person I become."

Luke said that when he arrived at Brown, he was a masculine-appearing lesbian, but had no plans to change sex. "I had questioned my sexuality, but not my gender," Luke said. Then he spent a year studying in Cuba, where people "were genuinely shocked when I said I was a woman. It was disorienting and scary. And I had to really think about it: am I a woman?" After returning from Cuba, he said, "I took more and more pains to hide my breasts and to pass as male." After meeting several female-to-male transsexuals, he said, "I realized I had options."

Luke said the reaction of "my immediate family has been awesome," though "my extended family is having a harder time. My grandparents still refer to me as `she.' "

Some parents might think that gender experimentation in college is just a phase. "So what if it is a phase - why is that a value judgment?" asked Daniel Bassichis, a Brown sophomore who is a friend of Luke's. "And if something goes wrong for Luke," Daniel said, "his friends will be here to support him."

But there are still issues for transgender students. Luke's voice sounds female, which makes him reluctant to "assert myself vocally." He is considering taking testosterone, which would lower his voice (as well as create facial hair and redistribute muscle), but hasn't been able to afford the hormone treatment. (At Smith, a therapist the college hired to serve as a transgender specialist told The Daily Hampshire Gazette last year that a small number of students there were taking testosterone to acquire male characteristics.)

As to whether he will have further surgery, Luke said he hasn't decided. "This is often the first thing people ask me — about whether I'll get surgery `down there,' and I think it is really weird," Luke wrote in an e-mail message.

Most doctors require patients hoping for gender-reassignment surgery to live as a member of the opposite gender for a full year. Luke and others see that standard as unreasonable - "for a guy who's 6-foot-2 to use ladies' rooms for a year is a recipe for disaster," he said.

Besides, the protocol negates the experience of students who don't want to be one gender or another, but something in between, Luke said. "It erases the space between male and female," he said. In an ideal world, he wouldn't have to conceal his female past in order to achieve a more male persona, he said. "I wouldn't be seen as male or female," he said, "but a female-to-male trans."

Luke will graduate this spring, but his effects on Brown may only be beginning. Some students predict that when Brown's new policies become known, more transgender students will want to apply. And if they do, "they can't just be plopped down," Daniel Bassichis said. "We have to make sure they feel safe here and can live the way they want to live."

Dr. Smith of Wesleyan said: "It takes a lot of courage to be out as a transgender person. I hope they'll be able to do it in the outside world the way they can in college."